Evacuation Procedures

System Evacuation-Figure 37:

System Evacuation-Figure 38:

Make sure the unit's tank has sufficient R-134a refrigerant for charging. Simultaneously press "RESET" and "ENTER" to enter the diagnostic mode. Then press "6." The display must show 16 kg (36 lb.) or more. If less than 16 kg (36 lb.) is displayed, add new refrigerant to the tank. Refer to the manufacturer's instructions for this procedure.

1. With the high side and low side hoses connected to the vehicle A/C system, open both the high side (Red) and the low side (Blue) valves on the unit's control panel.

2. Open both the red "Gas"(vapor) and the blue "Liquid" valves on the tank.


IMPORTANT: To remove all the air and properly dry the A/C system, the unit automatically goes to a minimum evacuation time of 20 minutes. It is possible to evacuate longer than 20 minutes. Press keys to enter time desired. New entry will show on the display. Press "ENTER" and the display will blink indicating input of data (figure 37).

3. Press "VACUUM" to start the vacuum pump. The display counts down the vacuum time from 20 minutes to zero to indicate operation time remaining. The display reads "RECYCLE" 5 seconds after the vacuum pump starts and continues while the process takes place.


IMPORTANT:
- Automatic refrigerant recycling during each evacuation is a feature of the ACR4 system. No action is required by the technician.

- The control panel "Moisture Indicator" must be "Green" during recycling verifying refrigerant moisture content is within specification. "Yellow" indicates a wet condition requiring a filter/drier cartridge change. Refer to the manufacturer's instructions for this procedure.

- Non-condensable gases (mostly air) are automatically vented from the tank during the recycling process. An audible sound of pressure release may be heard as this happens. This is a normal function.

4. At approximately the 17 minute mark on the display, (pump has run for 3 minutes) press "HOLD/CONT" key to stop vacuum pump (figure 38).

A. A "0" vacuum reading indicates a major system leak. Repair leak and restart evacuation procedure.

B. If a reading of 91-101 kPa (27-30 inch of Hg) is indicated, close the low side and high side valves. Observe the vacuum level for a few minutes as a leak check of the A/C system. If vacuum is not maintained, find and repair the A/C system leak before continuing.

C. If a reading of 91-101 kPa (27-30 inch of Hg) is maintained, open the high side and low side valves and press the "HOLD/CONT" key to restart the vacuum pump.

5. When the vacuum sequence has run the programmed time, the display shows "CPL" to indicate that evacuation is complete.


IMPORTANT:
- The vacuum pump oil must be changed frequently.

- When the pump has run for a total time of 10 hours, the message "OIL" will flash on the control panel display as a reminder to change the oil.

- If the "OIL" warning flashes during operation, press "CONT" and change the oil before the next operation. Refer to the manufacturer's instructions for this procedure.